The integration of spirituality into counselling and psychotherapy poses complex challenges. Personal spirituality, professional competency and ethical considerations may impact on trainees' experiences of integrating spirituality into therapy. This study adopted an inductive, qualitative approach to explore trainee counsellor/psychotherapists' experiences and perceptions of integrating spirituality into therapy. Six trainee counsellors and psychotherapists were recruited using purposive sampling from a professional counsellor and psychotherapist training institution in the UK. In‐depth, semi‐structured interviews were conducted, audio‐recorded and transcribed verbatim. Thematic analysis of the interviews revealed two overarching themes: spirituality provides support but needs a warning; and spirituality is relevant but undervalued. These themes encompass a wide range of trainee concerns associated with integrating spirituality into therapy. Participants reported that they felt unprepared to work therapeutically with clients' spiritual beliefs. However, the value of spirituality in providing support to both the trainee and their clients was highlighted by several participants. Some participants described integrating clients' spirituality as having a positive impact on the therapeutic relationship, but often felt threatening to the trainee. This research has implications that are important for counselling and psychotherapy training and developing enhanced consideration of client spirituality and the interpersonal environment in which therapy is delivered.